Remote signaling system



July 10, 1945. WHITE 2,380,282

REMOTE S IGNALING SYSTEM Filed Oct. 28, 1941 lnQentdr-fl Leo .D. White;

HisAKt W orneg;

Patented July 10, 1945 REMOTE SIGNALING SYSTEM Leo D. White, Schenectady, N. Y., assignor to General Electric Company, a corporation of New York Application October 28, 1941, Serial No. 416,841

5 Claims.

My invention relates to remote signaling systems and particularly to signaling stations in which a voltage of a predetermined polarity, corresponding to the position of a remote two-position device, is impressed across an electric circuit,

Heretofore, in such remote signaling systems,.it has been the practice to have the signaling currents of opposite polarity control a two-position polarized relay of the type which remains in the last operating position to which it is operated until it is energized by a current of the opposite polarity and to have the polarized relay selectively control the lighting of a group of electric lamps. Such an arrangement has the undesirable feature that if for any reason a polarized relay becomes stuck in either of its two operated positions or its coil becomes open-circuited, the relay remains in the last position to which it was operated, and there is nothing to indicate whether or not the position of the polarized relay and the signaling lamps controlled thereby correctly indicate the position of the corresponding remote device.

One object of my invention is to provide an improved arrangement of apparatus whereby the signaling lamps are more positively controlled to correctly indicate the position of the corresponding remote device.

Anotherobject of my invention is toprovide an improved arrangement of apparatus whereby no signaling lamps are lighted unless the signaling current is successful in effecting the energize.

tion ofa signaling relay each time the signaling current is transmitted.

My invention will be better understood from the following description when taken in connection with the accompanying drawing, the single figure of which diagrammatically illustrates a remote signaling system embodying my invention and the scope of my invention will be pointed out in the appended claims.

Referring to the drawing, RS represents a station where a plurality of two-position devices I are located, the positions of which areto be indicated at a. dispatchers oifice DO. In order to simplify the disclosure, only a single two-position device I is illustrated in the drawing, andthis is shown as an overcurrent circuit; breaker of the latched-closed type, having a trip coil iconnected in series relation with an electric circuit 3 so that contacts 4, which are closed when the main conthe auxiliary contacts 5, which are closed when vided, which, when in a predetermined position,

connects the neutral terminal-of a battery B1 to the line conductors L2, and depending upon the position of the circuit breaker I, either the positive or the negative terminal of the battery B1 is connected to the line conductor Ll Therefore, each time the selector switch A1 is in its predetermined position corresponding to the circuit breaker l, a voltage of a predetermined polarity corresponding to the position of the circuit breaker l is impressed across the line conductors LI and L2.

At the dispatchers ofiice DO, a multiple position selector switch A of the same type as switch A1 is provided. While the selector switches A and A1 are shown as rotary switches, it will be obvious to one skilled in the art that they may be of any other suitable type, examples of which are well known in the art and may be synchronously operated in any well-known manner. Since the details of the particular means for synchronously operating the switches A and A1 form no part of my present invention and are well known in the art, they have been omitted from the drawing in order to simplify the disclosure.

As shown, the selector switch A includes two banks of contacts, a and c, the corresponding movable wipers of which are respectively connected to the .line conductor Ll through the half wave rectifiers 6 and I, and a third bank of contacts b, the corresponding movable wiper of which is connected to the line conductor L2. The half Wave rectifiers 5 and l are so arranged that current can flow through the movable wiper of bank a only when the negative terminal of. the battery B1 is connected to the line conductor LI, and current can flow through the movable wiper of the bank 0 only when the positive terminal of the battery B1 is connected to the line conductor Ll.

The operating winding R1 of a relay R1 is connected between the line conductor L2 and the contact of banks. of switch A corresponding to the contact of bank (11 of switch A1 to which the auxiliary contacts 4 and 5 of circuit breaker l are connected. The operating winding GI of a relay G1 is connected between the line conductor L2 tacts of the circuit breaker are closed and with and a similar contact of bank 0 of switch A. The

relays R1 and G1 are provided with holding windings R2 and G2 respectively. When the relay R1 is in its energized position, its contacts 9 connect the holding winding R2 and a suitable impedance, such as a resistor ID, in series across a suitable source ofcurrent, such as the battery B. Similarly, when the relay G1 is in its energized position, its contacts I I connect the holding winding G2 and the resistor II! in series across a part of the battery 13. The mid-point of battery B is so connected to the movable wiper of the bank b of the switch A that a low resistance shunt circuit is completed around the holding winding of either of the relays, G1 or R1, that may be in its energized position at the time the shunt circuit is completed.

The position of the circuit breaker I is indicated at the dispatohers office by the manner in which the lamps R, G, and W are lighted. The red lamp R when lighted indicates that the circuit breaker I is closed. The green lamp G when lighted indicates that the circuit breaker I is open, and the white lamp W when lighted indicates that the position of the circuit breaker I does not agree with the position of a two-position manually operated disagreement key DK located at the dispatchers office.

The operation of the arrangement shown in the drawing is as follows: As long as the circuit breaker I remains closed and the disagreement key DK is in the position in which it is shown, the .various control devices, except the selector switches A and A1, remain in the positions in which they are shown in the drawing. At the remote station RS, the auxiliar contacts 4 of the circuit breaker I are closed so that during each revolution of the movable wipers of the switch A1 the negative terminal of the battery B1 is connected to the line conductor LI and the neutral terminal of the battery Bris connected to the line conductor L2 each time the switch A is in its position corresponding to the circuit breaker I. Consequently, a current of a predetermined polarity flows through the line conductors LI and L2 as long as the circuit breaker I remains closed.

At the dispatchers ofiice DO, an energizing circuit is completed across the battery B and the holdin winding R2 of th relay R1. This circuit also includes the resistor I and the contacts 9 of the relay R1. The red lamp R is also lighted since a circuit is completed therefor across the battery B through the contacts I2 of the energized relay R1.

Each time the synchronous selector switches A and A1 simultaneously occupy the positions corr sponding to the circuit breaker I, the holding winding R2 is deenergized since a shunt circuit is completed around this winding by the movable wiper of th bank I) of switch A. The relay R1, however, remains in its energized position since the signaling current which is then being transmitted is in a direction to flow through the half wave rectifier 6 and energizes the operating winding RI. Therefore, as long as the circuit breaker I remains closed, the relay R1 remains energized, and the red lamp R remains lighted.

It will now be assumed that the circuit breaker I operates so that its auxiliary contacts 4 are opened and its auxiliary contacts 5 are closed, thereby causing the positive terminal of the battery B1 to be connected to the line conductor LI whenever the selector switches A and A1 occupy their respective positions corresponding to the circuit breaker I. Under such conditions, the relay RI becomes deenergized and moves to its deenergized position and extinguishes the red lamp R. Since, however, the signaling current is in a direction to flow through the half wave rectifier I, the operating winding GI of the relay G1 is energized by the transmitted signaling current to effect the movement of the relay G1 to its energized position. The closing of the contacts I3 of the relay G1 completes a circuit for the green lamp G and also for the white lamp W, and the closing of the contacts II of the relay G1 prepares a circuit for the holding winding G2 50 that it becomes energized to maintain the relay G1 in its energized position after the selector switches A and A1 have rotated to the other positions in which the circuit of the operating winding GI is interrupted. The simultaneous lighting of the green and white lamps informs the dispatcher that the circuit breaker has moved to its open position. By moving the disagreement key DK to its other position, the dispatcher can extinguish the white lamp W.

Since both of the holdin windings R2 and G2 are prevented from being energized when th selector switches A and A1 are in a position to transmit a signaling current to either of the operating windings GI and RI, it is evident that if for any reason the signaling current is not transmitted when the selector switches are in that position or the signaling current fails to effect the operation of a relay to its energized position, neither the red lamp R nor the green lamp G is lighted. Consequently, there can be no incorrect lighting of the signal lamps.

While I have, in accordance with the patent statutes, shown and described my invention as applied to a particular system and as embodying various devices diagrammatically indicated, changes and modifications will be obvious to those skilled in th art, and I therefore aim in the appended claims to cover all such changes and modifications as fall within the true spirit and scope of my invention.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. In combination, two stations, two conductors interconnecting said stations, a movable device at one of said stations having two positions, two relays at the other station, each relay having an operating winding and a holding winding, a source of current, means controlled by each relay when in its energized position for connecting the holding winding thereof across said source, means for impressing across said conductors a voltage of a polarity dependent upon the position of said device, and means for efiecting simultaneously the deenergization of the holding winding of each energized relay and the connection of said operating windings across said conductors in such a manner that current flows through one of said operating windings only when a voltage of apredetermined polarity is impressed across said conductors and current flows through the other of said operating windings only when a voltage of the opposite polarity is impressed across said conductors.

2. In combination, two stations, two conductors interconnecting said stations, a movable device at one of said stations having two positions,

.two relays at the other station, each relay having an operating winding and a holding winding, a source of current, an impedance, means controlled by each relay when in its energized position for connecting the holding winding 2,380,282 thereof and said impedance in series across said source, two half wave rectifiers, means for impressing across said conductors a voltage of a polarity dependent upon the position of said device, means for effecting simultaneously the completion of a shunt circuit around the holding winding of each energized relay and the connection of one of said operating windings and one of said rectifiers inseries across said conductors so that current flows through said one of said operating windings only when a voltage of a predetermined polarity is impressed across said conductors and the connection of the other of said operating windings and the other of said rectifiers in series across said conductors so that current flows through said other of said operating windings only when a voltage of the opposite polarity is impressed across said conductors, and signaling means selectively controlled by said relays.

3. In combination, two stations, two conductors interconnecting said stations, a movable device at one of said stations having two positions, two relays at the other stationjeach relay having an operating winding and a holding winding, a source of current, an impedance, means controlled by each relay when in its energized position for connecting the holding winding thereof and said impedance in series across said source, and synchronously-operated multipleposition switching means at the two stations for effecting simultaneously when in predetermined corresponding positions the connection of the operating windings of said relays across said conductors in such a manner that current flows through one of said operating windings only when a voltage of a predetermined polarity is impressed across said conductors and current flows through the other of said operating windings only when a voltage of the opposite polarity is impressed across said conductors and the completion of a shunt circuit around the holding winding of whichever relay has its operating winding energized while said switching means are in said predetermined corresponding positions and the impression across said conductors of a'voltage of a polarity dependent upon the position of said device.

4. In combination, two stations, two conductors interconnecting said stations, a two-position device at one of said stations two relays at the other station, each relay having an operating winding and a holding winding, a source of current, means controlled by each relay when in its energized position for connecting the holding winding thereof across said source, synchronously-operated multiple-position selector switches at the two stations, and means controlled by said switches when in predetermined corresponding positions 'for effecting simultaneously the connection of said operating wind-' ings across said conductors in such a manner that a predetermined one of said operating winding is energized only when a voltage of a predetermined polarity is impressed across said conductors and the other operating winding is energized only when a voltage of the opposite polarity 1 is impressed across said conductors and the deenergization of each energized holding winding and the connection across said conductors of a voltage of a polarity dependent upon the position of said device. a

' 5. In combination, a circuit, two relays, each relay having an operating winding and a holding winding, means for impressing voltages of opposite polarities across said circuit, a source of current, an impedance, means responsive to the energization of an operating winding for connecting the associated holding winding and said impedance in series across said source, and switching means for effecting simultaneously the connection of said operating windings to said circuit in such a manner that current flows through" one of said operating windings only when a voltage of one polarity is impressed across said circuit and current flows through the other of said operating windings only when a voltage of the opposite polarity is impressed across said circuit and the completion of a shunt circuit around the holding winding of an energized relay while the associated operating winding is connected to said circuit.

LEO D. WHITE. 

